Screen printing machines are used during the fabrication of printed circuit boards. Planar substrates are advanced from a conveyor through the machine sequentially in a start-stop sequence during which, when the substrate stopped at a print location, a stencil is laid over the substrate and solder paste is spread over the stencil, with the solder paste being forced through openings in the stencil and onto the substrate. This can be a time intensive process with the constant starting and stopping of the conveyor.
Additionally, solder paste tends to build up in the stencil openings, which requires the fabrication process to be frequently stopped in order to clean the stencil. An additional problem with the current process is that, after the solder paste is applied, as the stencil is being lifted from the substrate, solder paste may also be lifted from the substrate, resulting in a less than desired application of the solder paste on the substrate.
It would be beneficial to provide a device that greatly reduces or eliminates the aforementioned deficiencies.